Nanoparticles coated with amphiphilic block copolymers

Abstract

The present provides amphiphilic block copolymer coated surfaces (e.g., nanoparticles, medical devices, etc.) and methods of preparing such surfaces. In certain embodiments, the present invention provides amphiphilic block copolymer coated single dispersed nanoparticles, which are stable in buffer (e.g., PBS) and have neutral but functionable surfaces, and methods of preparing the same.

We claim: 
     
         1 . A method of producing stable amphiphilic block copolymer coated single dispersed nanoparticles comprising:
 a) mixing a solution of amphiphilic block copolymer with a colloidal suspension of nanoparticles to generate a mixture, wherein said amphiphilic block copolymer comprises at least one functional group having an affinity for said nanoparticles;   b) treating said mixture at a temperature of above about 60 degrees Celsius to generate a treated mixture; and   c) adding at least a portion of said treated mixture to deionized water such that a solution is generated that comprises amphiphilic block copolymer single dispersed nanoparticles.   
     
     
         2 . The method of  claim 1 , wherein said nanoparticles comprise gold nanoparticles. 
     
     
         3 . The method of  claim 1 , further comprising d) removing said amphiphilic block copolymer coated single dispersed nanoparticles from said solution and mixing with deionized water. 
     
     
         4 . The method of  claim 1 , wherein said treated mixture is added dropwise to said deionized water. 
     
     
         5 . The method of  claim 1 , wherein said deionized water is in circular motion when said treated mixture is added thereto. 
     
     
         6 . The method of  claim 1 , wherein said temperature is above 100 degrees Celsius. 
     
     
         7 . The method of  claim 1 , wherein said temperature is about 60-160 degrees Celsius. 
     
     
         8 . The method of  claim 1 , wherein said mixing in step a) is conducted at about room temperature. 
     
     
         9 . The method of  claim 1 , wherein said treated mixture is cooled to about room temperature prior to step c). 
     
     
         10 . The method of  claim 1 , wherein said amphiphilic block copolymer comprises a polymer selected from the group consisting of: poly(2-(methacryloyloxy)ethyl phosphorylcholine), poly(2-(dimethylamino)ethyl methacrylate), poly(acrylic acid), poly(ethylene oxide), poly(ethylene glycol),poly(methyl methacrylate), polystyrene, poly(pyridyldisulfide ethylmethacrylate), poly(N-isopropylacrylamide), and poly(methacrylic acid). 
     
     
         11 . The method of  claim 1 , wherein said amphiphilic block copolymers comprise hydrophilic or hydrophobic polymer block having degree of polymerization in the range from 1 unit to 100 units. 
     
     
         12 . The method of  claim 1 , further comprising, prior to step a) preparing said colloidal suspension of nanoparticles by a top-down nanofabrication method using bulk metal as a source material. 
     
     
         13 . The method of  claim 12 , wherein said top-down nanofabrication method comprises applying a physical energy source to said bulk metal, said physical energy source comprising at least one of mechanical energy, heat energy, electric field arc discharge energy, magnetic field energy, ion beam energy, electron beam energy, or laser beam energy. 
     
     
         14 . The method of  claim 1 , wherein said colloidal suspension of nanoparticles comprises a population of nanoparticles wherein said nanoparticles have at least one dimension in the range of from 1 to 200 nanometers. 
     
     
         15 . The method of  claim 1 , wherein said functional group comprises a thiol group, an amine group, a phosphine group, a disulfide group or a mixture thereof. 
     
     
         16 . A composition comprising at least a portion of said amphiphilic block copolymer single dispersed nanoparticles prepared by the method of  claim 1 . 
     
     
         17 . Amphiphilic block copolymer coated single dispersed nanoparticles which are stable in buffer solution comprising: a population of single nanoparticles encapsulated in a shell formed by said amphiphilic block copolymers, said amphiphilic block copolymers contains at least one functional group having an affinity for the surface of said nanoparticles in its hydrophobic part and wherein said amphiphilic block copolymers coated nanoparticles have electrically neutralized surfaces and provide capability for further functionalization via thiol-disulfide exchange reactions. 
     
     
         18 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said functional group comprises a thiol group, an amine group, a phosphine group, a disulfide group or a mixture thereof. 
     
     
         19 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said amphiphilic block copolymer comprises hydrophobic or hydrophilic polymer block having degree of polymerization in the range from 1 unit to 100 units. 
     
     
         20 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said hydrophilic or hydrophobic polymer block of said amphiphilic block copolymer comprise a plurality of polymers selected from the group consisting of: poly(2-(methacryloyloxy)ethyl phosphorylcholine), poly(2-(dimethylamino)ethyl methacrylate), poly(acrylic acid), poly(ethylene oxide), poly(ethylene glycol), poly(methyl methacrylate), polystyrene, poly(pyridyldisulfide ethylmethacrylate), poly(N-isopropylacrylamide), and poly(methacrylic acid). 
     
     
         21 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said nanoparticles have at least one dimension in the range of from 1 to 200 nanometers. 
     
     
         22 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said amphiphilic block copolymer coated single dispersed nanoparticles are in powder form. 
     
     
         23 . The amphiphilic block copolymer coated single dispersed nanoparticles of  claim 17 , wherein said nanoparticles comprise gold.